closed loop issues

[dlrs14]

Can any one come up with a reason that the car will not go into closed loop?Just got my car put all back together, and had my tuner trying to write a new tune for all my new goodies. but for some reason it refuses to go into closed loop. Tried adjusting the temp and time for it to switch to closed loop....no dice. The o2's are brand new so I thought maybe somehow we had gotten rear o2's instead of front o2's. I got new ones and still no dice. Checked to see if the o2 wires somehow got pinched when we installed the engine and the harness seemed fine. The only thing I can think of is the CPU but am looking for other ideas or opinions. before I buy a new one. Any help is much appreciated.

 

[Dark_horse]

What brand of O2 sensors?

 

[Eel Mit]

Some tuners will shut off adaptives (read: stay in open loop) to get a base tune (which keeps the oxy sensor feedback from adjusting the tune (via Fuel Trims). This is usually done when a tuner asks you to do a stepped rpm log (idle for 10sec, then 1500rpm for 10sec, then 3000rpm for 10sec, etc).

Might want to check and see if your tuner left adaptives switched off.

 

[dlrs14]

What brand of O2 sensors?

OE ford.

Some tuners will shut off adaptives (read: stay in open loop) to get a base tune (which keeps the oxy sensor feedback from adjusting the tune (via Fuel Trims). This is usually done when a tuner asks you to do a stepped rpm log (idle for 10sec, then 1500rpm for 10sec, then 3000rpm for 10sec, etc).

Might want to check and see if your tuner left adaptives switched off.

Thanks I'll check with him on that.

 

[BruceH]

How do you know it's staying in open loop?

 

[dlrs14]

If I understand correctly, he was watching the voltage on the sensors and they were staying steady at .7 volts?? and they were supposed to be raising and lowering instead of being steady..

Worked with it more today and it looks like voltage might be a cause. It idle, voltage was about 12.1, but if he raised the rpm to over 1k, voltage would go up to 13.2 and the o2's would start switching. Gonna double check the connections at the alt on sat and also have the alt checked. Tuner's not gonna be available again till the 20th so that gives me time to get a new alternator if need be.